UPPER CRUSTAL RESISTIVITY STRUCTURE OF THE EAST PACIFIC RISE NEAR 13-DEGREES-N

被引：37

作者：

EVANS, RL ^{[1
]}

CONSTABLE, SC ^{[1
]}

SINHA, MC ^{[1
]}

COX, CS ^{[1
]}

UNSWORTH, MJ ^{[1
]}

机构：

[1] UNIV CALIF SAN DIEGO,SCRIPPS INST OCEANOG,INST GEOL & PLANETARY PHYS,LA JOLLA,CA 92093

来源：

GEOPHYSICAL RESEARCH LETTERS | 1991年 / 18卷 / 10期

关键词：

D O I：

10.1029/91GL02305

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

An active source electromagnetic (EM) sounding has been conducted on the axis of the East Pacific Rise (EPR) at 13-degrees 10' N. 1D inversion and modelling techniques, seeking resistivity as a function of depth, have been applied to 8 Hz amplitude data collected along the ridge crest. Resistivity is seen to increase monotonically between 50 m and 1 km below the seafloor, increasing from approximately 1-OMEGA-m. We observe no intrinsic difference in upper crustal resistivity structure between the rise axis and 100 000 year old crust. Inferred surface porosities of 20% are larger than those recorded in 5.9 my old crust in DSDP hole 504B. Our data do not require, and lack sufficient information for, the reliable inclusion of a conductive termination to the model below 1.2 km.

引用

页码：1917 / 1920

页数：4

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